Taxonomy categorie

Hello,
I created a custom post type “fournisseurs” with a taxonomy called “categoriefournisseur” : I would like to display only the posts which have the taxonomy “categoriefournisseur” set as “one” so I did :
[loop type=fournisseurs categoriefournisseur=catone orderby=title]
[field title-link]
[/loop]
But it also display posts that do not have the “one” taxonomy set,
Can you help me ?
Regards,
Jeanne